What is 49 to the negative power 1/2?

So say you have just 49 raised to the 1/2, that is equivocal to the square root of 49, which is 7. Instead, you have 49 raised to the negative half power, so all you need to do is move that term to the denominator of its fraction. You now have 1/49^(1/2) which turns out to be 1/7

Logical equivalent of the give question is its contrapositive